1. ATMS 360 – University of Nevada Reno CO 2 Measurements Presented by Nick Burgener, Sam Taylor, and Jasmine White

2. Why are CO 2 measurements important?  Carbon Dioxide is the primary greenhouse gas emitted by human activities  Combustion of fossil fuels is the main cause  In the last 25 years, emissions have increased by 7% http://www.epa.gov/climatechange/ghgemissions/gases/co2.html

3. Why are CO 2 measurements important?  Greenhouse gases are naturally regulated by earth processes  However, humans have created an excess of carbon dioxide, throwing the balance off  This increase in greenhouse gases leads to sunlight being trapped and contributes to global warming  It also dissolves in the oceans, causing them to become more acidic  This raised acidity causes decomposition of coral and other calcium based organisms http://www.mnn.com/earth-matters/climate-weather/stories/co2-101-why-is-carbon-dioxide-bad

4. Why are CO 2 measurements important?  By measuring the levels of CO 2 in the air, we can gain a better understanding of how our actions affect the planet  This could help us to lower our emissions  If nothing else, it will show us how much we have already changed our world and how important it is to make changes

5. Measuring CO 2 levels – Telaire 6004

7. http://www.co2meter.com/blogs/news/6010192-how-does-an-ndir-co2-sensor-work

8. Measuring CO 2 levels  IR light of the specific wavelength which interacts with carbon dioxide is directed through the chamber  The sensor picks up what light still passes through  Whatever light was absorbed and not detected by the filter can be related to the amount of CO 2 molecules present

9. Measuring CO 2 levels  I = I o e -nLα  L is length of tube  α is the absorption cross section of CO 2 (constant)  n is the number of CO 2 molecules (what we want)  Because we know I o and I from the sensor, the number of CO 2 molecules can be easily calculated

12. Calibration for Temperature and Pressure

13. Equations used by the CO 2 Sensor

14. Calibration for Temperature and Pressure Cont.

15. 400 ppm Calibration Before the calibration was applied, teensy card 4 appeared to be very inaccurate. However, once the card was calibrated for 400 ppm, it lined up nicely with the rest of the cards. Card 3 appeared to have some strange values.

16. Data Analysis  Non-calibrated Time Series: data from all four cards varied from each other.  After calibration, data was averaged around 400ppm between 17:45 - 18:45 (10:45 am – 11:45 am).  Fluctuations in data could suggest tampered levels of CO 2 at surface.  Fluctuations in data could be caused by card mechanics.

17. Card Status  Card 1 was described to be standard as it found 400ppm during personal data collection.  Card 2 followed similar pattern despite modifications/location difference.  Card 4 recorded outlier data before calibration. Card 2 Location

18. Improvements? Yes!  Hypothesized Card 3 was short-circuited due to contact with a metal pole.  Securing/Examining surrounding area to minimize interference.  Making certain each card worked appropriately.  Test runs versus actual runs.  More cards for larger data pool.  Ensuring proper activation/warm-up time window.

19. Questions? Comments? Stories? …Anything?